You can put this solution on YOUR website! log(base 7)4x-log(base7)(x+3)=log(base 7)x
You can rewrite the left (based on log rules):
log(base 7)(4x/(x+3)) = log(base 7)x
log(base 7)(4x/(x+3)) - log(base 7)x = 0
log(base 7)(4x/x(x+3)) = 0
(4x/x(x+3)) = 7^0
4x/x(x+3) = 1
4x = x(x+3)
4x = x^2+3x
0 = x^2-x
0 = x(x-1)
.
x = {0,1}